Projects per year
Abstract
We study the response of the Earth's magnetosphere to fluctuating solar wind conditions during interplanetary coronal mass ejections (ICMEs) using the Grand Unified Magnetosphere-Ionosphere Coupling Simulation (GUMICS-4). The two ICME events occurred on 15-16 July 2012 and 29-30 April 2014. During the strong 2012 event, the solar wind upstream values reached up to 35 particles cm(-3), speeds of up to 694 km s(-1), and an interplanetary magnetic field of up to 22 nT, giving a Mach number of 2.3. The 2014 event was a moderate one, with the corresponding upstream values of 30 particles cm(-3), 320 km s(-1) and 10 nT, indicating a Mach number of 5.8. We examine how the Earth's space environment dynamics evolves during both ICME events from both global and local perspectives, using well-established empirical models and in situ measurements as references. We show that on the large scale, and during moderate driving, the GUMICS-4 results are in good agreement with the reference values. However, the local values, especially during high driving, show more variation: such extreme conditions do not reproduce local measurements made deep inside the magnetosphere. The same appeared to be true when the event was run with another global simulation. The cross-polar cap potential (CPCP) saturation is shown to depend on the Alfven-Mach number of the upstream solar wind. However, care must be taken in interpreting these results, as the CPCP is also sensitive to the simulation resolution.
Original language | English |
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Pages (from-to) | 561-579 |
Number of pages | 19 |
Journal | Annales Geophysicae |
Volume | 37 |
Issue number | 4 |
DOIs | |
Publication status | Published - 11 Jul 2019 |
MoE publication type | A1 Journal article-refereed |
Keywords
- CAP POTENTIAL SATURATION
- HIGH-LATITUDE
- GEOMAGNETIC-ACTIVITY
- PLASMA TRANSPORT
- MHD SIMULATION
- MAGNETOSPHERE
- MODEL
- SHOCK
- IONOSPHERE
- STORMS
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Dive into the research topics of 'GUMICS-4 analysis of interplanetary coronal mass ejection impact on Earth during low and typical Mach number solar winds'. Together they form a unique fingerprint.Projects
- 2 Finished
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Shocks and Magnetosheaths in the Heliosphere
Alho, M., Pulkkinen, T., Järvinen, R., Kallio, E., Knuuttila, O. & Lakka, A.
01/09/2017 → 31/08/2022
Project: Academy of Finland: Other research funding
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The turbulent magnetosheath: the impact on magnetospheric and radiation belt plasma properties
Dimmock, A. & Pulkkinen, T.
01/09/2015 → 14/01/2018
Project: Academy of Finland: Other research funding